Refuse compacting device

ABSTRACT

A telescopic fluid cylinder for use in a waste compactor having a rod fixed to the compactor, an intermediate cylinder surrounding the rod and supporting the main ram, an auxiliary ram surrounding the intermediate cylinder and mounted in and movable relative to the main ram. A sequence valve responsive to fluid pressure in the system actuates the auxiliary ram for jam clearing purposes.

United States Patent 1191 Toppins Apr. 9, 1974 [54] RE U E COMPACTING V E 3,608,476 9/1971 Price et a1 100/49 3,613,559 10/1971 Buisson 100/49 [75] Invenm" Charles TWPmS, Kmxvluei 3,621,775 11/1971 Dedio et a]. 100/295 Tenn. 3,734,005 5/1973 Vogel 100/295 [73] Assignee: Carrier Corporation, Syracuse, NY.

Primary ExaminerBilly J. Wilhite [22] Ffled' 1972 Attorney, Agent, or Firm--Donald F. Daley [21] Appl. No.: 309,394

' [57 ABSTRACT [52] US Cl 100/49 100/179 g 35 55 A telescopic fluid cylinder for use in a waste compac- [51] Int Cl B30!) 15/16 tor having a rod fixed to the compactor, an intermedi- [58] Fieid 269 R 43 ate cylinder surrounding the rod and supporting the 106/48 52 main ram, an auxiliary ram surrounding the intermediate cylinder and mounted in and movable relative to [56] References Cited the main ram. A sequence valve responsive to fluid pressure in the system actuates the auxiliary ram for UNITED STATES PATENTS jam clearing purposes 3,384,007 5/1968 Boje et al 100/295 3,603,245 9/1971 Pioch 2 Claims, 6 Drawing Figures mmn mva 91914 $802,336

saw 2 0F 3 FIG. 3

WENTEMPR 1914 $802,336

sum 0F 3 FIG. 5

1 REFUSE COMPACTING DEVICE BACKGROUND OF THE INVENTION This invention relates generally to refuse compacting devices and more specifically, to a fluid power system for use in refuse compacting devices.

Refuse compactions devices of the type using a reciprocating compaction ram generally fall into two categories. The first utilizes a ram to compact refuse into a closed chamber wherein a bale of refuse is ejected from the chamber after compaction by forward movement of the ram into the chamber. This type of compaction device is usually used in large installations where the bales of refuse are loaded into truck bodies or portable containers. Large volumes of refuse can be handled and the available space in the truck body or container can be efficiently utilized. The second type of compaction device ejects a substantially continuous mass of compacted refuse by moving a ram to force refuse through a funnel shaped opening. The pressure of the ram forces the refuse through the funnel causing compaction by extrusion and eventually ejection through the smaller end of the funnel. A device of this type is disclosed in the Bojc et al, U.S. Pat. No. 3,384,007, issued May 21, I968. Machines of this type are utilized for intermittent, unattended operation. A common usage is in residential apartments wherein trash and waste are deposited by tenants into chutes which deposit the trash into a bin which feeds the waste compactor.

In both the closed chamber and funnel type of compactorsall types of normal waste material, including cartons and irregular shaped objects are deposited for compaction. The non-uniformity of material results in varying amounts of pressure required to compact the material and force it through the funnel or into the chamber. Occasionally material will jam, resulting in excessive pressure buildup, causing the ram to stall or go through repeated cycling to break up the jam. In the prior art, devices such as the Boje et al, patent cited above, a smaller auxiliary ram concentrically located in the center of the main ram has been used. The main ram is driven forward by a hydraulic cylinder and, upon occurrence of a jam, the small auxiliary ram is forced forward through a separate hydraulic system in an attempt to break up the jam ahead of the main ram. Devices of this type have been successful, however, they increase the cost of the compactor unit, in that they require separate hydraulic systems for each ram and a control system associated therewith. The Boje et al, U.S. Pat. No. 3,384,007, for example, utilizes three separate hydraulic cylinders with valving and control between the cylinders.

The present invention is usable in both closed chamber and funnel type of compactors and eliminates the need for separate hydraulic systems for the main ram and the jam clearing or auxiliary ram while, at the same time, maintaining the operation and function of each ram. One hydraulic system can be used to drive both the main ram for compaction purposes and the auxiliary ram for jam relieving purposes.

SUMMARY OF THE INVENTION It is an object of this invention to drive a compaction ram and a jam clearing ram in a refuse compactor from a single hydraulic system;

type of refuse compactor. It should be understood that it is also an object of this invention to provide a refuse compaction device with an automatic jam clearing capability by utilizing the jam clearing ram as the hydraulic cylinder in the fluid system used to power the compaction ram;

it is also an object of this invention to reduce the fluid system piping and space requirements in a refuse compactor by telescoping the fluid cylinder used to power the main compaction ram.

These, and other objects of this invention are attained by means of a hydraulic main ram head mounted in a refuse compaction device and having an auxiliary ram mounted in the main ram which serves as part of the fluid cylinder used to drive both the main ram and the auxiliary ram. Fluid pressure sequence valves are incorporated in the fluid system to drive the auxiliary ram when the main ram encounters pressure build-up during compaction of refuse.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be hereinafter more fully described with reference to the accompanying drawings in which:

FIG. 1 is an isometric view of a funnel type refuse compacting device with portions broken away to show internal structure;

FIG. 2 is a cross sectional view of a compaction ram and the fluid cylinders used in the compacting device shown in FIG. 1;

FIG. 3 is a sectional view of the rams and fluid cylinder of the compactor shown in FIG. 1, with the main ram in the extended position;

FIG. 4 is a cross sectional view of the rams and fluid cylinders of the compactor shown in FIG. 1, with the main ram and the auxiliary ram in the extended position;

FIG. 5 is a diagramatic representation of a hydraulic system usable with-the present invention;

FIG. 6 is a diagramatic representation of an electrical circuit usable with the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT The invention is disclosed herein in a ram and funnel the invention is applicable to any type of compactor which utilizes a main compaction ram and an auxiliary or jam clearing ram.

Referring to the drawings, and specifically to FIGS. 1-4, there is shown a waste material compactor embodying the present invention. The waste compactor shown in FIG. 1 receives refuse material from a chute 2 wherein waste material is accumulated prior to compaction. The chute deposits refuse or waste material into a compaction chamber 4 enclosed in an elongated casing or body 6. The compactor assembly is usually mounted on a foundation or base indicated generally as 8. Waste material deposited in the chute 2 falls into the compaction chamber 4 and is subsequently compressed and forced through an exit opening 10 into a funnel shaped member 12. The large end of the funnel 12 receives refuse material from the exit opening 10, and as the material is extruded through the funnel into the smaller end, it is compacted for subsequent disposal. In the end of the funnel 12, there is a cylindrical tube 14 from which the refuse material is ejected into suitable containers.

Within the casing 6 there is slidably mounted a main compaction ram 16 which is capable of traversing the compaction chamber 4 to force waste material into the funnel 12. An auxiliary ram 18 is mounted in the center of the main ram 16 and is utilized to clear jammed waste material ahead of the main ram and may also be used to force waste material into and through the funnel 12 at the end of the stroke of the main ram. It is not essential to the operation of the present invention that the auxiliary ram be located in the center of the main ram. Particularly in compactors of the type wherein the ram is not cylindrical, it may be desirable to locate the auxiliary ram in a position other than the center of the main ram. I-Ieretofore, compactors of this type have utilized separate hydraulic cylinders to drive the main ram and the auxiliary ram. In the present invention the auxiliary ram comprises the cylinder portion of the hydraulic system used to drive both the main ram and the auxiliary ram. The main ram, the auxiliary ram, the piston rod and an intermediate section all telescope together to provide a compact unitary fluid power system to drive the rams through the compaction chamber.

The internal structure of the hydraulic system and of the auxiliary ram can be seen in the sectional views of FIGS. 2-4. A fixed rod 20 which serves as a hydraulic piston and as a fluid line is secured to the rear of the casings 6 by means of a pivotal connecting bracket 22. The rod 20 has a pair of hydraulic ports 24 and 26. The port 24 is the fluid inlet port for the extend mode of operation and the port 26 is the drain port in the extend mode. In the return mode of operation the port 26 becomes the inlet port and the port 24 becomes the drain port. In each mode of operation the inlet port is connected to high pressure fluid and the drain port is connected to a fluid reservoir tank. The rod 20 has a hollow interior which forms a fluid passage chamber 28. The fluid passage chamber is connected to the port 26 while a fluid line 30 is connected to the port 24 and extends through the passage chamber 28 and through the head end 32 of the rod 20.

An intermediate section 34 of tubular shape surrounds the rod 20 and serves as a hydraulic cylinder relative to the piston function of the rod 20. The intermediate section 34 is comprised of a cylindrical shell 36 and a head 38 which hydraulically seals the forward end of the cylinder. The fluid line 30 is opened to a chamber 40 formed between the head 38 of the intermediate section and the head 32 of the rod 20. There are sealing rings or bushings 42 at the rear of the intermediate section 34 and sealing rings 44 at the forward end of the rod 20 which serve to hydraulically seal the fluid in the chamber 40 and in an intermediate expansion chamber 46 formed between the interior surface of the intermediate section 34 and the outside surface of the rod 20. Sealing rings or bushings 42 and 44 also serve to guide the movement of the intermediate section 34 relative to the rod 20. The sealing rings 42 are secured to the inside of the intermediate section 34 while the sealing rings 44 are secured to the outside of the rod 20.

The shell 48 of the main ram 16 is secured to the intermediate section 34 by means of a rigid connecting rod 50. The means of connecting the intermediate section 34 to the main packer ram 16 is illustrative only. Any suitable rigid connection may be used. As shown herein, however, the rod 50 is connected to the inside of the shell 48 and to a connector ring 52 secured about the outer surface of the intermediate section 34 at the rearward portion thereof. Linear movement of the intermediate section 34 will produce a corresponding movement in the main packer ram 16 by means of the connecting rod 50.

The auxiliary packer ram 18 is concentrically mounted about the intermediate section 34 and comprises an outer shell or casing 54 and a compaction head 56. The compaction head 56 and the intermediate section head 38 form an expansion chamber 58 within the inner diameter of the auxiliary ram 18. The intermediate section head 38 has a sequence valve 60 and a check valve 62 interconnecting the expansion chambers 40, 58. The operation of the sequence valve 60 and the check valve 62 will be described in more detail below. A fluid drain line 64 extends from the sequence valve 60 through the rod head 32 to the passage chamber 28. The line 64 is mounted for sliding movement at the point where it passes through the head 32. The line 64 is of a length sufficient to allow the end of the line to be in the chamber 28 when the compactor is in the fully extended position. The outer surface of the intermediate section 34 forms one wall of a third expansion chamber between the intermediate section 34 and the auxiliary packer ram 18. Chamber 70 is sealed by a sealing ring or bushing 66 secured to the rear inner wall of the auxiliary ram 18 and a bushing or sealing ring 68 secured to the outer forward surface of the intermediate section 34.

When the compactor is functioning in the extend mode of operation high pressure fluid is admitted through the port 24 through the line 30 to the expansion chamber 40. The expansion chamber 40 is essentially the head end of the hydraulic cylinder. The high pressure fluid acts against the inside of the head 38 of the intermediate section or cylinder 34 and against the head 32 of the rod 20. Since the rod 20 is fixed at bracket 22 the intermediate cylinder 34 advances to the right, as seen in FIG. 3. The intermediate section or cylinder 34 carries the main packer ram 16 and the auxiliary ram 18 forward until the position shown in FIGS. 1 and 3 is reached. That is, the main ram traverses the compaction chamber 4 forcing refuse forward through the funnel 12. If the refuse ahead of the main compaction ram jams, causing the main ram to stall, the pressure in chamber 40 will increase until the actuating pressure of sequence valve 60 is reached. The sequence valve 60 is set for a predetermined pressure which, when encountered in the chamber 40, will allow the fluid to pass through the head 38 of the intermediate cylinder. High pressure fluid passing through the sequence valve 60 into the expansion chamber 58 forces the auxiliary ram 18 forward ahead of the main ram 16. At this point the intermediate cylinder 34 acts as a piston relative to the auxiliary ram 18. The intermediate section 34 remains stationary and the auxiliary ram 18 is forced forward by the action of the high pressure fluid in the chamber 58. The auxiliary ram will move forward into the jammed refuse material clearing the jam and forcing part of the refuse material forward into the funnel 12. Forward movement of the auxiliary ram continues until the retaining ring 72 on the rear of the auxiliary ram 18 triggers a limit switch SW-3 mounted on the inside of the head of the main ram 16. Actuation of the limit switch SW-3 will cause the high pressure fluid to be switched to the port 26 and the port 24 will be switched to a low pressure reservoir, all as explained in detail below with respect to the operation of the circuit and hydraulic diagrams.

With the port 24 connected to the reservoir, the pressure in chamber 40 drops allowing sequence valve 60 to close. High pressure fluid entering port 26 provides pressure to the passage chamber 28. The high pressure in the passage chamber 28 passes through a port 74 extending between the passage chamber 28 and the expansion chamber 46 between the rod and the intermediate cylinder 34. High pressure fluid in the expansion chamber 46 acts on the bearings or seals 42, 44, causing the intermediate cylinder 34 to be moved in the rearward direction. The high pressure fluid acting on the smaller surfaces of the bearings 42, 44, is sufficient to overcome the low pressure fluid in chamber 40 acting on the end of the rod 20 and the inside of the head 38. As the cylinder 34 moves in a rearward direction, the chamber 40 decreases in size and fluid in the chamber 40 is forced through the line out the port 24 to the reservoir. The high .pressure fluid in the passage chamber 28 passes through the fluid line 64 to the sequence valve 60 assuring that the sequence valve 60 closes at the same time the switch SW-3 is closed.

The rearward movement of the intermediate cylinder 34 causes the main ram 16 to be, withdrawn back through the compaction chamber 4 to its original or starting position. In addition, the rearward movement of the intermediate cylinder 34 moves a port 76 into open flow relationship with the expansion chamber 46. The port 76 is in the outer wall of the intermediate cylinder 34 and provides a fluid opening between the expansion chamber 46 and the expansion chamber 70 formed between the outer surface of the intermediate cylinder 34 and the inner surface of the auxiliary ram 18. High pressure fluid in the chamber 70 acts against the bearings 66, 68 to produce rearward movement of the auxiliary ram 18. Here again, the action of the high pressure fluid against the surfaces of the bearings 66, 68 is sufficient to overcome the action of the fluid in the expansion chamber 58 acting on the head 38 of the intermediate cylinder and the head 56 of the auxiliary ram. The fluid pressure build-up in the chamber 58 by the rearward movement of the auxiliary ram 18 is released through the one-way check valve 62 to the chamber to the fluid line 30 and the port 24. The high pressure fluid in the chamber 70 continues to move the auxiliary ram rearward until the auxiliary ram is again positioned inside the main ram, as shown in FIG. 2. The compactor is then in position to be recycled for further compaction of the material in the compaction chamber 4.

OPERATION The operation of the compactor shown in FIGS. 1-5 will be described with reference to the hydraulic system and the electrical circuitry shown in FIGS. 5, 6 respectively. The passage chamber 28 and the fluid line 30 of the hydraulic cylinder rod 20 are connected to a fluid pump 78 through a hydraulic four-way directional valve 80. The pump 78 is driven by a motor 82 and pumps fluid from a reservoir 84 through line 86 to the four-way directional valve 80. A hydraulic line 88 connects the four-way directional valve to the fluid line 30 of the rod 20 and a hydraulic line 90 connects the fourway valve to the passage chamber 28 in the rod 20. A system relief valve 89 is provided in the line 86 to prevent excessive pressure build-up in the system.

A spring 92 holds the four-way directional valve in a straight through position wherein the pump 78 pumps fluid through the line 86, through the four-way directional valve to the line 88 leading to the fluid line 30 of the rod 20. In this position fluid is free to move from the expansion chambers 46, through line 90, through the four-way directional valve back to the reservoir 84. A solenoid sol-l has its plunger connected to the four-way directional valve 80 to actuate the valve to a position wherein fluid from the pump 78 will pass through the line 86 to the four-way directional valve, through the four-way directional valve to line I leading to the passage chamber 28. Hydraulic fluid in the expansion chambers 40, 58 is free to move through the fluid line 30, through the line 88, through the fourway directional valve 80 back to the reservoir 84. A pressure switcls 94 is mounted in line 86 or 90 to respond to excess pressure in the system to disconnect solenoid sol-l, allowing the spring 92 to reverse the position of the four-way directional valve.

A light or sonic sensing switch 96 is mounted in the hopper 2 to detect the presence of refuse in the hopper and initiate operation of the compactor. The switch 96 has contacts SW-s mounted in the main power line to the compactor. When the light or sonic beam is broken, the contacts SW-s close, energizing the compacting circuit. A master switch SW-Ml is also mounted in the main power line to the compactor so that the entire compactor may be shut downv to prevent operation at any time. The master switch SW-Ml must be closed prior to operation of the compactor. A manual switch SW-M2 is mounted in the compactor circuit in parallel with the contacts SW-s of the sensing switch 96, to allow manual operation of the compactor. In the event there is insufficient refuse in the hopper 2 to actuate the sensing switch 96, the compactor may be operated by manually closing the switch SW-M2.

Closing of the contacts of the sensing switch SW-s or the manual switch SW-M2, energizes the circuit and provides power through a counter 98 to a relay R1. The relay R1 has a set of normally open contacts Rl-l which are in parallel with the contacts of the sensing switch SW-s and the manual switch SW-M2 and which provide a holding circuit for the relay R1. Operation of the compactor allows the refuse in the hopper 2 to be depleted and the beam of switch 96 to be restored. The contacts SW-s are normally open, cutting off power to the compactor circuit. The holding circuit and the contacts Rl-l maintain power to the circuit throughout the cycle of operation. The counter 98 can be set to allow a predetermined number of cycles of operation prior to de-energizing relay R1 which, in turn, opens contacts Rl-l to shut down the compactor. The counter 98 is pulsed by sets of contacts to switches SW-l and SW4. The switch SW-l is a limit switch located on the inside of the casing 6 at a position to be actuated by the return movement of the main ram 16. The switch SW-4 is located on the intermediate cylinder 34 and is actuated by the auxiliary ram 18. Both SW-l and SW-4 must be closed to pulse counter 98, therefore, both the main ram and the auxiliary ram must be in the start of cycle position withdrawn from the compaction chamber. If, for example, it is determined that the hopper 2 and the compaction chamber 4 hold approximately five times the volume of the compaction chamber, then the counter would be set to operate five cycles each time the sensing switch 96 is interrupted. Each time that the main ram 16 and the auxiliary ram 18 return to their retracted position they would actuate switches SW-] and SW-4 pulsing the counter 98.

Closing of the sensing switch SW-s also energizes the motor 82 and provides power to a second relay R2 through a second set of contacts to switch SW-l. The line to relay R2 also has two sets of normally closed contacts for a second limit switch SW-2 and a third limit switch SW-3 mounted in series with the relay R2 and in parallel to the contacts oflimit switch SW-l. The limit switch SW-2 is mounted in the compaction chamber 4 in a position to be actuated by the main ram head at the end of the compaction stroke.

Relay R2 has two sets of contacts, the first set R2-l being normally open and mounted in the line to relay R2 parallel to contacts of switch SW-l. Contacts R2-l provide a holding circuit for the relay R2. A second set of contacts R2-2 for the relay R2 are also normally open and control the power to the solenoid sol-l.

Prior to operation, main ram 16 is in the retracted position shown in FIG. 2 and the switches SW-l and SW-4 are held in a closed position. When refuse is accumulated in the hopper 2 the circuit to the switch 96 is interrupted and the normally open contacts SW-s are closed, energizing relay R1 and providing the holding circuit through contacts Rl-l. The motor 82 is energized, driving pump 78 to provide high pressure fluid to the system from reservoir 84. With the switch SW-l in a closed position, the relay R2 is energized, closing the holding circuit through contacts R2-1 and the circuit to solenoid 501-1 through contacts R2-2. With the solenoid energized, the four-way directional valve 80 is moved to the position wherein high pressure hydraulic fluid is supplied to the fluid line 30 and to expansion chamber 40. Fluid in the expansion chamber 40 forces the intermediate cylinder 34 forward carrying the main ram 16 through the compaction chamber. Forward movement of the main ram 16 releases the switch SW-l allowing the contacts of switch SW-l to return to their normally open positions. The solenoid sol-l continues to be energized by means of power through contacts SW-2, SW-3 and R2-l to relay R2 and through contacts R2-2 to the solenoid sol-1. When the main ram 16 advances through the compaction cycle to the position shown in FIG. 1, the switch SW-2 is actuated and the normally closed contacts SW-2 are open, breaking the circuit to relay R2. De-energization of relay R2 allows the contacts R2-2 to open, de-energizing solenoid sol- 1. The four-way directional valve 80 is then moved under the action of the spring 92 to the position wherein high pressure fluid is supplied from the pump 78 to the passage chamber 28, through line 90. Pressure in the passage chamber 28 and the expansion chamber 46 between the outer surface of the rod 20 and the inner surface of the intermediate cylinder 34, causes the intermediate cylinder 34 to move back towards the retracted position. Release of the switch SW-2 allows the contacts SW-2 to revert to their normally closed position, however, the contacts R2-1 are now in an open position since relay R2 has been deenergized. When the main ram 16 is in the fully retracted position, it actuates limit switch SW-l, again pulsing the counter through the closed contacts of switch SW-4. lf the preset number of cycles has been completed, the counter 98 will de-energize relay R1 cutting off the entire circuit. However, if the counter has not reached the preset number then the second set of contacts to the switch SW-l which also closed, reenergizes relay R2, repeating the compacting cycle.

In the event that the full compaction cycle cannot be completed because of excess resistance ahead of the ram, then the fluid pressure in the system will increase until sufl'icient pressure is reached to actuate the sequence valve 60. The sequence valve 60 allows fluid from the expansion chamber 40 to pass through the head 38 of the intermediate cylinder 34 to the expansion chamber 58. The fluid in the expansion chamber 58 will move the auxiliary ram 18 forward ahead of the main ram 16, breaking up the refuse jam.

When the auxiliary ram 18 has moved forward through its full cycle, the limit switch SW-3 is actuated by the rear portion of the casing of the auxiliary ram 18. Actuation of the switch SW-3 opens the circuit to the relay R2 which de-energizes the solenoid sol-l in the same manner as described for the actuation of the switch SW-2. De-energization of the solenoid sol-l allows the four-way directional valve to move to the position wherein high pressure fluid is provided to the passage chamber 28 causing the intermediate cylinder 34 to move rearward under the action of high pressure fluid entering the expansion chamber 46 through the port 74. When the intermediate cylinder 34 and the main ram 16 have moved to their original start cycle positions,the switch SW-l is actuated and high pressure fluid in the expansion chamber 46 passes through port 76 to the expansion chamber 70. At this time, the cycle is not re-energized since the switch SW-4 has not been actuated and a set of contacts to switch SW-4 mounted in parallel to the contacts of switch SW-l which energized the relay R2, remain open. When the auxiliary ram has also returned to its fully retracted position, both switches SW-l and SW-4 are closed, pulsing counter 98 and re-energizing the relay R2. If the counter 98 has not completed its full number of cycles, the relay R1 will continue to hold the circuit closed, allowing another cycle of operations.

in the event that the full compaction cycle cannot be completed and the jam ahead of the auxiliary ram provides sufficient pressure to prevent forward movement through the full cycle of the auxiliary ram, then the pressure build-up in the system will increase until sufficient pressure is reached to actuate a pressure switch 94. The pressure switch 94 is located in the electrical circuit to the relay R2 and when actuated will open its normally closed contacts, de-energizing the relay R2 and the solenoid sol-l. When this situation is reached prior to the completion of the compaction cycle, the spring 92 moves the four-way directional valve 80 to the return stroke position, thus, the main ram 16 and the auxiliary ram 18 will return to the original retracted position and actuate switches SW-l and SW-4 to initiate a complete new cycle of operation.

Having thus described the invention relative to the preferred embodiment disclosed, it is understood that various changes may be made by one skilled in the art, without departing from the spirit and scope of the invention.

I claim:

1. A telescopic fluid operated ram for use in a waste compacting device of the type wherein waste material is compressed by ram type members in a compaction chamber including:

a packer ram mounted in the waste compacting device for reciprocating movement through the compaction chamber;

an auxiliary ram concentrically mounted in the packer ram for reciprocating movement relative to the packer ram;

an intermediate cylinder telescopically mounted in the auxiliary ram and secured to the packer ram for movement with the packer ram;

a rod member secured at one end and extending into the intermediate cylinder in a piston-like relationship;

means to provide pressurized fluid between the rod and the intermediate cylinder to drive the intermediate cylinder and the main packer ram forward through the compaction chamber; and

means responsive to the fluid pressure to pass fluid between the intermediate cylinder and the auxiliary ram upon detection of a predetermined fluid pressure to thereby move the auxiliary ram relative to the packer ram.

2. in a waste material compacting device of the type utilizing reciprocating rams to.compress waste material, a compaction system including:

a packer ram reciprocably movable through a compaction chamber and having a packer head and extending rearwardly from the head;

an auxiliary ram-mounted in the body of the packer ram and extending through the head thereof for reciprocating movement relative to the packer ram;

said auxiliary ram having a packing head and a hollow, rearwardly extending body;

an intermediate hollow cylinder mounted in the auxiliary ram and having a cylinder head and a body with an outside diameter smaller than the inside diameter of the auxiliary ram;

seals mounted on the intermediate cylinder in contact with the auxiliary ram body to form a first expansion chamber between the intermediate cylinder head and the auxiliary ram head;

seals mounted on the inside of the auxiliary ram body in contact with the intermediate cylinder to form a second expansion chamber between the intermediate cylinder body and the auxiliary ram body;

a piston rod fixed at one end and extending into the intermediate cylinder and having a diameter smaller than the inside diameter of the intermediate cylinder;

seals mounted on the rod in contact with the intermediate cylinder body to form a third expansion chamber between the rod and the intermediate cylinder head;

seals mounted on the inside of the intermediate cylinder body in contact with the rod to form a fourth expansion chamber between the rod and the intermediate cylinder body;

means connecting said intermediate cylinder to the main ram for movement therewith;

a fluid supply system including a fluid passage chamber and a pressurized fluid source;

means connecting the fluid system to the third expansion chamber;

means responsive to fluid pressure in third expansion chamber to pass fluid under pressure from the third expansion chamber to the first expansion chamber;

means connecting the fourth expansion chamber to the fluid system and the second expansion chamber to the fourth expansion chamber;

means to allow passage of fluid from the first expansion chamber to third expansion chamber when the pressure in the third expansion chamber is lower than the pressure in the first expansion chamber; and

means to alternately connect the pressurized fluid source to the means connecting the third expansion chamber to the fluid system and the means connecting the fourth expansion chamber to the fluid system to thereby alternately provide pressurizing fluid to the third and first expansion chambers for forward movement of the packer ram and the auxiliary ram, and to the fourth and second expansion chambers for rearward movement of the packer ram and auxiliary ram. 

1. A telescopic fluid operated ram for use in a waste compacting device of the type wherein waste material is compressed by ram type members in a compaction chamber including: a packer ram mounted in the waste compacting device for reciprocating movement through the compaction chamber; an auxiliary ram concentrically mounted in the packer ram for reciprocating movement relative to the packer ram; an intermediate cylinder telescopically mounted in the auxiliary ram and secured to the packer ram for movement with the packer ram; a rod member secured at one end and extending into the intermediate cylinder in a piston-like relationship; means to provide pressurized fluid between the rod and the intermediate cylinder to drive the intermediate cylinder and the main packer ram forward through the compaction chamber; and means responsive to the fluid pressure to pass fluid between the intermediate cylinder and the auxiliary ram upon detection of a predetermined fluid pressure to thereby move the auxiliary ram relative to the packer ram.
 2. In a waste material compacting device of the type utilizing reciprocating rams to compress waste material, a compaction system including: a packer ram reciprocably movable through a compaction chamber and having a packer head and extending rearwardly from the head; an auxiliary ram mounted in the body of the packer ram and extending through the head thereof for reciprocating movement relative to the packer ram; said auxiliary ram having a packing head and a hollow, rearwardly extending body; an intermediate hollow cylinder mounted in the auxiliary ram and having a cylinder head and a body with an outside diameter smaller than the inside diameter of the auxiliary ram; seals mounted on the intermediate cylinder in contact with the auxiliary ram body to form a first expansion chamber between the intermediate cylinder head and the auxiliary ram head; seals mounted on the inside of the auxiliary ram body in contact with the intermediate cylinder to form a second expansion chamber between the intermediate cylinder body and the auxiliary ram body; a piston rod fixed at one end and extending into the intermediate cylinder and having a diameter smaller than the inside diameter of the intermediate cylinder; seals mounted on the rod in contact with the intermediate cylinder body to form a third expansion chamber between the rod and the intermediate cylinder head; seals mounted on the inside of the intermediate cylinder body in contact with the rod to form a fourth expansion chamber between the rod and the intermediate cylinder body; means connecting said intermediate cylinder to the main ram for movement therewith; a fluid supply system including a fluid passage chamber and a pressurized fluid source; means connecting the fluid system to the third expansion chamber; means responsive to fluid pressure in third expansion chamber to pass fluid under pressure from the third expansion chamber to the first expansion chamber; means connecting the fourth expansion chamber to the fluid system and the second expansion chamber to the fourth expansion chamber; means to allow passage of fluid from the first expansion chamber to third expansion chamber when the pressure in the third expansion chamber is lower than the pressure in the first expansion chamber; and means to alternately connect the pressurized fluid source to the means connecting the third expansion chamber to the fluid system and the means connecting the fourth expansion chamber to the fluid system to thereby alternately provide pressurizing fluid to the third and first expansion chambers for forwaRd movement of the packer ram and the auxiliary ram, and to the fourth and second expansion chambers for rearward movement of the packer ram and auxiliary ram. 